The collection of vast amounts of personal data via the Internet has raised a variety of privacy-related concerns. During interactions with web service providers, users may disclose information to the service provider in order to facilitate a transaction. Privacy issues can be raised regarding the collection of, use of, sharing of, and level of control exercised over sensitive data, in addition to user access to disclosed sensitive data. Sensitive data can include a user's real name, address, email address, phone number, birth date, all or part of a user's social security number, demographic information, health information or other data that a user may regard as sensitive or personal in nature.
Internet privacy involves the ability to not only control information revealed by a user during an online session, but to also control who can access the disclosed information. For example, a user may disclose data to a web service provider without knowing that the data will be shared with another entity. As another example, a user may provide one piece of information to a first web service, and another piece of information to a second web service, that, when put together, can identify the user within a particular degree of certainty. In some situations, if a user was aware of the information being shared and the impact the disclosure can have on the user's privacy, the user may decide not to share the information or can accept that the user's identity may be known to the web service.